Molten-salt fabrication of (N,F)-codoped single-crystal-like titania with high exposure of (001) crystal facet for highly efficient degradation of methylene blue under visible light irradiation

Abstract

Single-crystal-like TiO 2 is claimed to be a very promising material among various catalysts. In this study, the (N,F)-co-doped single-crystal-like TiO 2 was prepared by a new molten mixing process in which the mixed nitrates were used both as a morphology modifier and an N-doping agent at the same time. The prepared samples also had well-developed (001) facet due to the addition of HF. The HF can also be an F doping agent to the material. The co-doping of N and F can diminish the band gap of TiO 2 from 3.05 to 2.93 eV, therefore visible light can be used effectively by the material. In addition, NO and fluorine ions existing on the surface of the sample can also help its photocatalyticity. Therefore, the photocatalytic performance of the as-prepared sample was effectively improved.

Synthesis of Composite Titanate Photocatalyst via Molten Salt Processing and Its Enhanced Photocatalytic Properties

“…The combination was treated to a 24 h hydrothermal reaction at a temperature of 150 • C. After centrifugation and drying, the sample was mixed with NaNO 3 -KNO 3 mixed salt in a molar ratio of 1:5, where the molar ratio of NaNO 3 to KNO 3 was 1:1. Based on the previous exploration of our research group, it is difficult to generate titanate products at 600 • C [37][38][39]. Therefore, the corresponding titanium salt samples were obtained via calcining at 600, 650, 700, 750, and 800 • C for 4 h after sufficient washing and drying.…”

Modulation of the photocatalytic activity and crystallinity of F-TiO2 nanoparticles by using green natural carboxylic acids

“…Therefore, finding a balance between the sol–gel and hydrothermal synthesis with the incorporation of organic acids for the formation of highly active photocatalytic TiO 2 systems is one of the main goals of this study. In addition, our interest is also focused on preparing F-doped TiO 2 materials as these preferentially form ultrareactive {001} facets 20–22 and exhibit optimal structural properties for applications in photocatalysis. 23–26…”